ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Reference completely ab initio 6-3G and nonempirical 3G/MODPOT (ab initio effective core model potential) LCAO-MO-SCF calculations (using the same valence atomic orbital basis) were performed for a series of boron hydrides (B4H10, B5H9, B5H11, and B6H10) and a test 3G/MODPOT + VRDDO (variable retention of diatomic differential overlap for charge conserving integral prescreening) calculation were also performed for B5H9, B6H10, and B10H14. The agreement between the ab initio 6-3G and the corresponding 3G/MODPOT calculations was excellent for valence orbital energies, gross atomic populations, and dipole moments. The results also compared favorably to previous ab initio minimum STO basis results of Lipscomb and coworkers. The 3G/MODPOT + VRDDO calculations verified that for such spatially compact molecules (such as boron hydrides, which are fragments of polyhedra), the VRDDO procedure does not result in a noticeable savings in computer time for molecules of the size and shape of B5H9 and B6H10, in contrast to the savings previously realized for organic molecules of comparable atomic size. However, the agreement in calculational results between the 3G/MODPOT and the 3G/MODPOT+VRDDO results was still as extremely close as it had been for the organic molecules.3G/MODPOT calculations were also carried out for B8H12, B9H15, B10H14, B10H14-2, 1,2-C2B4H6, and 1,6-C2B4H6 and the results compared to the previous minimum STO basis results. For B10H14, the 3G/MODPOT+VRDDO method led to savings in computer time of 28% over the 3G/MODPOT method itself.The agreement of the 3G/MODPOT results with available experimental photoelectron spectral data for B5H9 and 1,6-C2B4H6 was as good as that of the previous ab initio minimum STO basis calculations.
Additional Material:
12 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560120514
Permalink
